The present invention relates to stage lighting devices incorporating light valves for projecting images on a stage.
Stage lighting devices incorporating light valves for the projection of images are known in the art. Stage lighting devices incorporating light valves are used to project patterns on a stage. Before electronic light valves, stage lighting devices used metal stencil patterns that were indexed on a wheel to produce the projected patterns upon the stage.
U.S. patent to U.S. Pat. No. 4,779,176 to Bornhorst titled xe2x80x9cLight pattern generatorxe2x80x9d describes glass substrates with aluminum coatings that are used as projection patterns in a lighting device. U.S. Pat. No. 5,113,332 titled xe2x80x9cSelectable mechanical and electronic pattern generating aperture modulexe2x80x9d to Richardson describes an electronic aperture or light valve used to generate the patterns projected from a lighting device. U.S. Pat. No. 5,758,956 titled xe2x80x9cHigh intensity lighting projectorsxe2x80x9d to Hutton describes a controllable image quality projection gate providing advanced visual effects. Other types of electronic light valves have also been used with lighting devices. U.S. Pat. No. 5,828,485 titled xe2x80x9cProgrammable light beam shape altering device using programmable micromirrorsxe2x80x9d to Hewlett describes a digital micromirror device (xe2x80x9cDMDxe2x80x9d) that is used to alter the shape of light that is projected onto a stage.
The prior art stage lighting devices are designed around a single light valve as the projection gate. The inventors have optimized their inventions to work best as a lighting device. Many inventors prefer the single light valve system as it may have a reduced cost over multiple light valve systems. High End Systems (Trademarked) of Austin, Tex. has found success with a multiple light valve projector in combination with a positioning mirror. The device called a Catalyst (Trademarked) is used like a periscope that mounts to the front of a video projector. It allows static images or moving video to be projected anywhere within a 360xc2x0 by 180xc2x0 hemisphere of movement. Images can be manipulated limitlessly in real-time from a dedicated control console. The preferred projector type of the prior art is a three light valve system. More information can be found at: Http://www.highend.com/pdfbin/NewCatalyst.pdf. The device is limited however as it uses a conventional multiple light valve projection system and can only produce a limited color palette.
In the prior art a single light valve is used. An aperture device containing filters or multiple aperture devices containing filters are located between a lamp producing white light and a single light valve to change the color of the light from the lamp sent to the single light valve. The single light valve systems can not do full color images unless they spin an aperture device containing color filters of red, blue and green in front of the single light valve. The aperture device containing the colors of red, blue and green is rotated, in the prior art, at a certain frequency in sync with the single light valve to produce a full color image. Because each color is only on for a third of the time, much of the energy from the lamp is lost. An example of this technique is shown at http://howstuffworks.lycos.com/projection-tv5.htm
With existing regular video projection, three light valves are used with the white light produced from a lamp separated into red, green and blue as more of the light from the lamp is used to produce a full color image.
The problem is that for a video projection device built for video the red, green and blue colors are specially specified.
The present invention discloses a lighting device using multiple light valves which provide an improved contrast ratio from devices of the prior art. The lighting devices of embodiments of the present invention are capable of projecting a wide range of available colors.
The present invention allows a greater array of colors both saturated and less saturated to be used by first allowing the widest production of red, green and blue by a color separation system or device and then modifying the colors from the color separation system with aperture devices that contain color filters. Aperture devices modify the separated colors.
It is one object of the present invention to construct a multiple light valve lighting device with an improved lighting color palette.
It is yet another object of the present invention to construct a multiple light valve lighting device with an improved contrast ratio.
It is yet another object of the present invention to transmit commands over a communication system to the multiple light valve lighting devices where custom color palettes may be selected remotely.
It is yet another object of the present invention for the multiple light valve device to automatically improve the contrast ratio based upon the program material.
It is yet another object of the present invention for the multiple light valve lighting device to shutter the outputs of the individual light valves upon a command over the communication system.
It is yet another object of the present invention for the multiple light valve lighting device to shutter all of the individual light valves to produce a black out.
It is an object of the present invention to provide an apparatus comprising a lamp which produces a first light which may be a white light, a first light valve, a second light valve, and a first aperture device or a first electronically switchable filter. The first electronically switchable filter and electronically switchable filters generally may be considered to be aperture devices. The first aperture device or the first electronically switchable filter function as selectively variable color separators. The first aperture device or the first electronically switchable filter each can be placed in a first state where the first light is separated into a first color light and a first residual light and a second state where the first light is separated into a second color light and a second residual light. The first color light has a corresponding first frequency and the second color light has a corresponding second frequency. Varying the state of the first aperture device from the first state to the second state, varies a first output of the first aperture device from the first frequency of the first color light to the second frequency of the second color light. Varying the frequency of light produces different color lights. In this application a frequency of light is also referred to as a color light. The color light may have a frequency range or bandwidth as known in the art.
This means that light going to the red light valve may generally be close to the color red but may be selected to be orange, medium red, or dark red for example. Such different shades of red may be considered a first color and a second color. I.e. orange and medium red may be considered different colors or a first color and a second color, respectively. The first light valve receives the first color light in the first state and the second color light in the second state. The second light valve receives at least a portion of the first residual light when the first aperture device is in the first state or the second residual light when the first aperture device is in the second state.
The present invention in one embodiment discloses a lighting device comprised of a first device, a first light valve, a second light valve, a combining device, and a projection lens device. The first device may be comprised of a color separator device and an aperture device. The first device may separate a first light from a light source into a first frequency light and a second frequency light, wherein the first and second frequencies are different. The first and second frequency lights may be applied to first and second light valves, which produce first and second light valve output lights, respectively. Each of the first and second light valve output lights have a frequency. The combining device may combine the first light valve output light and the second light valve output light to produce a combined light at an output of the combining device. The projection lens device may receive the combined light and project light from the projection lens. The frequency of the first light valve output light or the frequency of the second light valve output light can be selectively varied, by, for example, varying the state of the first aperture device from the first state to the second state, which may vary a first output of the first aperture device from a first frequency light to a second frequency light; by an aperture device located in the first device; or by the combining device.